The casting of unknown actor James Howson, who is in his early 20s and from Leeds, shouldn't be surprising given that Heathcliff was described in the original book as a "dark-skinned gypsy" and "a little lascar" – a 19th-century term for Indian sailors. Among the many screen adaptations of Wuthering Heights – which include musicals, TV serials, a Mexican version directed by Luis Buñuel and an ill-conceived teen romcom produced by MTV – a dark-skinned actor has never been given the role.

Even though Brontë passed away in 1848, one can easily imagine the writer turning in her grave at the prospect of so many white actors portraying her "little lascar" throughout history. As any Briton who's ever watched an American war film knows, it's common practice for history to be rewritten during the film-making process, with writers often pushing the boundaries of artistic licence to its very limits.

But whether a film character is based on a real-life person or entirely fictional, it's surely unacceptable for directors to meddle with their skin colour or ethnicity to suit their own – or supposedly their audiences' – prejudices. Laurence Olivier played Heathcliff in the 1939 Hollywood version when cinema's ethnic sensitivities were perhaps not so acute, but things ought to have been different by 1992 when Ralph Fiennes starred as the hero opposite Juliette Binoche. Revered and respected though he was at the time, Fiennes hardly embodies the dark-skinned street urchin described by Brontë. Hollywood may not have been a multicultural melting pot in the early 90s but are we really to believe that not a single black or dark-skinned actor might have been up to the job? It suggests a certain amount of arrogance, and even cowardice on behalf of directors who were not prepared, or too fearful of audience reception, to give the role to an actor whose ethnicity came anywhere close to matching that of the character.

So it is a bold and significant move by Arnold to buck this unsavoury trend and cast a non-white actor in the role. As in the book, the bleak, rugged countryside and class issues are central to her film. In contrast to the original story, however, race plays a pivotal role: Heathcliff is racially abused by his adopted brother and referred to as a "nigger" on several occasions. In fact, as Xan Brooks points out, there are many parts of Arnold's version that Brontë herself might not recognise – particularly the spiky dialogue and substitution of blunt, animalistic expressions of sexuality for tender, old-fashioned romance. However, Brontë fans will now for the first time see a character that bears a much closer physical resemblance to Brontë's original creation.

Arnold was clearly unwilling to compromise on her vision: she declined to audition well-known actors in favour of open casting calls and at one point even scoured a Romany camp in search of her dark-skinned Heathcliff. Sticking with tradition is usually seen as the safe option as far as adaptations are concerned, but Arnold has actually taken a calculated risk by casting an unknown actor in such a high-profile role.

Arnold deserves praise for taking such a positive step into territory where many others have refused to tread. But will the first mixed-race Heathcliff be hailed as a landmark move by filmgoers? Or will audiences continue to accept the film industry's whitewashing of minority ethnic characters at face value?

Director Andrea Arnold talks about her new movie, American Honey, which stars Shia LaBeouf and explores the US phenomenon of ‘mag crews’ – rootless young outsiders who rove the midwest selling magazine subscriptions

An Afro-Caribbean Heathcliff, a Caucasian anime hero and an all-black take on Tennessee Williams. How far can such 'race-bending, or 'race-lifting', go towards redrawing racial boundaries on film and stage?